class=img_thumbleft>As the population of the U.S. climbs toward 300 million, a mark it is set to surpass in October, Minnesota has seen its own big growth. The state topped 5 million in 2002, according to estimates, and projections have Minnesota adding another half a million people each decade for the next 30 years. Unrivaled by any state in the Midwest (see chart after the jump), Minnesota has the fastest growth rate in the region. Between 2000 and 2005, Minnesota's population increased by 4.3 percent, compared to Wisconsin's 3.2 percent, Iowa's 1.4 percent and North Dakota's -0.9 percent, according to estimates released last month by the U.S. Census Bureau.

This feat, however, is little to brag about, as Minnesota is just the leader of laggards. The country's growth rate is 5.3 percent, putting every state in the region below the national average.

The plight of the rusting Midwest--with its stagnant manufacturing and rented-out farms--is barely news. "Some areas of the upper Midwest have experienced very long-term out-migration of young people," said Tom Gillaspy, the state demographer for Minnesota. "There are some counties in the Midwest where a quarter of the population is over 65."

With this uneven age distribution in mind, states have tried to take action, though options are limited. A year ago, the Iowa Legislature considered eliminating income tax for anyone under 30, a plan that received much press but fizzled out.

Between 2000 and 2005, Iowa had a net "internal migration" of -41,000 people--a figure representing all the people who moved to Iowa (from within the U.S.) minus all of those who moved away.

Minnesota lost residents to internal migration as well (a net loss of 16,000 people in the same time period), though its effects were not as dear as in many other states in the region. North Dakota netted a loss of an estimated 18,000 people; Michigan lost 165,000; and Illinois bled an estimated 391,000 residents.

The other big factor for Minnesota's relative success is its "natural increase", or births minus deaths. With what is widely considered to be a relatively healthy population, Minnesota saw a low death rate. Matched with an average birth rate, the state had an estimated 1.8 births to every death between 2000 and 2005, the best ratio in the region. (The highest in the country was in Utah, with 3.7 births to every death.)

These trends have lead to a rapidly expanding Twin Cities metro, where exurban developments constantly spring up, replacing fields of soy and corn with cul-de-sacs and SuperTargets.

Scott County, southwest of the Cities, serves as the epicenter for this explosion: Since 1990, it has nearly doubled in population, from 57,846 to an estimated 112,623 people in 2004.

Dakota County, south of St. Paul, has added more than 100,000 people since 1990, going from 275,000 residents to an estimated 383,000 in 2004.

These suburbs and exurbs have a demographic makeup that might make Iowa legislators' mouths water: By far the most populous age group in Scott County 2000 was 35 to 39-year-olds.